In response to the Queensland fruit fly outbreak, the Ventura County agricultural commissioner, Korrine Bell, told reporters that California was “facing an agricultural crisis.” She urged residents: “Please, don’t pack a pest.”

The Mediterranean fruit fly is among the most undiscerning, and therefore, destructive — it has made its home inside more than 250 kinds of produce, including avocados, tomatoes, mangoes and walnuts, and has spread across parts of Europe, the Middle East, Australia and the Americas. California — which grows a majority of the nation’s fruit and nuts — is among the states most at risk, according to the United States Department of Agriculture.

Although the Mediterranean fly does not pose a current risk to California’s crops, the potential repercussions, if the situation is not managed properly, could be devastating, agricultural experts say. “Growers would go out of business; packing houses would go bankrupt; the damage would be in the billions,” said James Cranney, the president of the California Citrus Quality Council. It would be, he added, an “untold level of catastrophe.”

The eradication plan for the flies in Leimert Park is part of a broader preventive release program that is run by the state Food and Agriculture Department and the U.S.D.A., and airdrops millions of sterile male Mediterranean fruit flies across counties in Southern California throughout the year. In the nearly three decades since its inception, the program has helped reduce the number of infestations by more than 90 percent, according to the state.

The barren males are bred at labs in Hawaii and Guatemala (where the pest is already present), and as pupae are dyed pink or orange to distinguish them from fertile flies. Each week, more than 200 million of the fluorescent insects are shipped to Los Alamitos, Calif., for distribution. After being carefully incubated, and later, fed a diet of sugar, water and an algae derivative, the adult flies are then loaded into planes with “release chutes” that evenly distribute them.